I do not know the current models, but, in selecting the right camera for snorkeling with kids my main selection criterias would be:
1) wrist strap to attach your camera on your wrist
2) sufficient depth rating. Some cameras go up to 15m without separate case, and many small point-and-shoots have inexpensive cases up to 40m. I would avoid cameras that are just "water proof" or rated to 3m or 5m.
3) wide angle lense
4) for shallow snorkeling (less than 3-5m?) you might not need any filters at all
5) a bright LCD screen and preferably a hood as well
6) short trigger delay preferred or you'll miss a lot of opportunities
This is great, thanks. Hope you don't mind some followup questions. Regarding your (1), do you recommend any particular wrist strap for attaching the camera at the wrist (which I assume does not include dangling as from a conventional strap)? Regarding (3), how wide do you recommend (in 35mm equivalents), as the Oly has an optional wide-angle attachment lens rated for underwater (more than just 3m, I believe) and I wonder whether to purchase it? Regarding your (5), you mention not needing a filter, but would the filter hurt in many situations, and might it help on some shots? Thanks.